Medical Definition of Catechol-O-methyltransferase

Catechol-O-methyltransferase: COMT. An enzyme that catalyzes the degradation of catecholamines, including the neurotransmitters dopamine, epinephrine, and norepinephrine. COMT is also important in the metabolism of catechol drugs used in the treatment of hypertension, asthma, and Parkinson disease. A genetic polymorphism (a common normal variant) in COMT contributes to the responses to pain and stress.